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            <h2 class="title" style="clear: both"><a id="log_limits"></a>Log file limits</h2>
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      <p>Log filenames and sizes impose a limit on how long databases may be
used in a Berkeley DB database environment.  It is quite unlikely that an
application will reach this limit; however, if the limit is reached,
the Berkeley DB environment's databases must be dumped and reloaded.</p>
      <p>The log filename consists of <span class="bold"><strong>log.</strong></span> followed by 10 digits, with
a maximum of 2,000,000,000 log files.  Consider an application performing
6000 transactions per second for 24 hours a day, logged into 10MB log
files, in which each transaction is logging approximately 500 bytes of data.
The following calculation:</p>
      <pre class="programlisting">(10 * 2^20 * 2000000000) / (6000 * 500 * 365 * 60 * 60 * 24) = ~221</pre>
      <p>indicates that the system will run out of log filenames in roughly 221
years.</p>
      <p>There is no way to reset the log filename space in Berkeley DB.  If your
application is reaching the end of its log filename space, you must do
the following:</p>
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          <li>Archive your databases as if to prepare for catastrophic failure (see
<a class="xref" href="transapp_archival.html" title="Database and log file archival">Database and log file archival</a>
for more information).</li>
          <li>Reset the database's log sequence numbers (see the <span class="bold"><strong>-r</strong></span> option
to the <a href="../api_reference/C/db_load.html" class="olink">db_load utility</a> for more information).</li>
          <li>Remove all of the log files from the database environment.  (This is the
only situation in which all the log files are removed from an environment;
in all other cases, at least a single log file is retained.)</li>
          <li>Restart your application.</li>
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